ABSTRACT
The rotating biological contactor process is a secondary biological wastewater treatment system. It consists of large-diameter plastic media, which is mounted on a horizontal shaft and placed in a concrete tank. Wastewater flows through the process just once, with no need for recycling of effluent. Because the attached biomass is continuously growing, there is also no need for recycling of sludge. The rotating contactor process is similar in function to the trickling filter process in that both operate as fixed-film biological reactors. Passing wastewater over the media, as in a trickling filter, results in a near-laminar flow of wastewater down through the media. This affects the trickling filter process operation in several ways. The process are: Short contact time, poor wastewater contact, ineffective sloughing, controlled sloughing, no nuisances, efficient aeration, controlled contact and aeration, high degrees of treatment, process stability, flexibility, maintenance and power consumption, ease of nitrification and sludge characteristics.
